Classifications

• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/065—Traffic control systems for road vehicles by counting the vehicles in a section of the road or in a parking area, i.e. comparing incoming count with outgoing count
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/01—Detecting movement of traffic to be counted or controlled
  • G08G1/0104—Measuring and analyzing of parameters relative to traffic conditions

Definitions

• the invention relates to a method for detecting malfunctions in road traffic within a sector to be monitored, in which the number and speed of the vehicles passing through the measuring cross-sections are continuously recorded as measuring data at a measuring cross-section at the beginning and end of the sector, while being collected and cyclically added to finite, consecutively numbered measuring intervals Average values of the traffic volume and the speed are compressed and then evaluated, each measurement cross section comprising all lanes which can be driven in one direction of travel.
• variable message signs Due to the constantly increasing road traffic, influencing systems with variable message signs are used more and more frequently for its collective control on multi-lane roads, the control of which uses different methods for fault detection in road traffic.
• the motivation for investing in such systems and for developing associated procedures for fault detection is based on the fact that the variable traffic signs can be used to carry out warnings of the subsequent traffic moving towards fault locations, in the form of consequential accidents.
• Of particular importance here is the most reliable and rapid detection of the fault, ie a shortening of the critical time between the occurrence and the protection of a fault.
• Traffic is currently recorded using measurement methods that record measurement data from individual vehicles based on so-called measurement cross-sections. It is common to monitor individual sectors, each limited by a measurement cross-section at the beginning and end, i.e. Sections of a traffic line.
• the quantity "traffic volume” is defined as the number of registered vehicles per unit of time, from which, for example, [units / min] results as their unit.
• route system functions are formed with the aid of suitable correlation methods, from which the route-related traffic parameters "travel time” (and thus the average cruising speed) of the vehicle collectives considered in the route section between the input and output measurement cross sections and the "traffic density" in the route section between the input and output measurement cross sections can be derived.
• a disadvantage of signal conditioning which is usually carried out in the form of exponential smoothing, is that parameters have to be set and set for each measuring cross-section and for all individual data, which results in a very high parameterization effort.
• Statistical methods have the disadvantage that they are not significant because of the missing population in the individual decision.
• the invention has for its object to propose a method with which, regardless of the traffic situation with the least possible loss of time and with little data processing and measurement technology disruptions in road traffic can be detected.
• the continuous, dynamic balancing of the vehicles additionally entering the monitored sector enables fault detection to be achieved which is very reliable and largely independent of the respective traffic situation. If the traffic situation is trouble-free, the traffic flowing into the monitored sector can be found taking into account the averaged speeds, driving behavior, sector length and a distribution assumption at the sector exit.
• the method according to the invention takes into account which proportion of the vehicles measured during a detection cycle will leave the monitored sector in the same cycle, only in the following cycle or in a later cycle. For this purpose, the proportion factors are determined, with the aid of which the vehicle collective recorded at the beginning of the sector of an acquisition cycle is divided over the two cycles during which its shares are likely to leave the sector again.
• the disadvantages of methods which only consider the measurement data of the measurement cross sections at the beginning and end of the sector at the same time and independently of the route topology and with which only a relatively unreliable fault detection is possible even when constructing complex analysis criteria are reliably avoided by the method according to the invention.
• the data processing outlay for the method according to the invention is at a very low level, which is most comparable to that for methods for accident detection on the basis of local measured variables.
• the method according to the invention can also be used very economically, since an additional direct connection between the route stations assigned to the measuring cross sections, as is absolutely necessary in methods based on route-related traffic parameters, and because of the high reliability of the accident detection, the distances between two measuring cross sections , ie the sector length can be very large.
• the predicted value of the traffic volume can now be determined from the counted vehicles, an assumption about the temporal distribution of the detected vehicles over the detection cycle T and the determined proportion factors of the vehicles.
• BDQ i exceeds a certain limit value (for example, depending on the traffic condition)
• a fault message is triggered.
• the fault message can vary depending on the severity of the fault, ie the level of BDQ i , in order to prompt the following vehicles to behave appropriately in the special case.
• a particularly advantageous embodiment of the invention consists in that the calculation of the forecast value of the traffic intensity is carried out separately for each lane in one direction of travel and a cyclical comparison is carried out between the sum of the forecast values of all traffic lanes in one direction of travel and the value of the traffic intensity determined at the measuring cross section at the end of the sector.
• the reliability of the forecast value can be increased with the aid of this individual consideration of the lanes, since more precise assumptions for the driving behavior and the time distribution of the vehicles can be made for a single lane.
• Individual forecasts for each lane with specific driving behavior (right lanes: truck traffic, left lane (l) lane: overtaking traffic) and subsequent summation thus deliver better results than a sum formation before the forecast, which leads to a loss of information.
• fuzzy logic be used to trigger the fault message, in which, in addition to the number of additional vehicles remaining in the sector, at least one input variable describing the traffic condition is used.
• a further development of the method according to the invention further consists in that the fuzzy logic delivers an output variable which describes the type of the accident.
• the describable uncertainties as to how the drivers of the vehicles make use of their range of behavior, which is dependent on the particular traffic condition, in their driving style can be taken into account in an advantageous manner.
• the effect is a further increase in the reliability of the method according to the invention.
• the invention is further developed so that only the traffic volume and the speed of the trucks for fault detection are evaluated as measurement data, provided that the share of trucks in the total traffic volume exceeds a certain limit.
• the measurement data acquired at the sector end of a sector are simultaneously used as measurement data at the beginning of the sector of a subsequent sector.
• Each measurement cross section represents at the same time represent the measurement cross-section at the sector end of sector i and at the beginning of sector i + 1.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Traffic Control Systems (AREA)
• Road Signs Or Road Markings (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=7760344

Family Applications (1)

Country Status (5)

Cited By (11)

Families Citing this family (21)

Family Cites Families (7)

• 1996
  • 1996-04-26 EP EP96106579A patent/EP0740280B1/fr not_active Expired - Lifetime
  • 1996-04-26 ES ES96106579T patent/ES2135134T3/es not_active Expired - Lifetime
  • 1996-04-26 DE DE59602517T patent/DE59602517D1/de not_active Expired - Lifetime
  • 1996-04-26 AT AT96106579T patent/ATE182709T1/de not_active IP Right Cessation
  • 1996-04-29 US US08/639,967 patent/US5684475A/en not_active Expired - Fee Related

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